Frog of the Week

Holy Cross Frog (Notaden bennettii)

Holy Cross Frog
photo by wikiuser Tnarg 12345

Common Name: Holy Cross Frog, Crucifix Frog, and Crucifix Toad
Scientific Name: Notaden bennettii
Family: Myobatrachidae – Australian Ground Frog family
Locations: Australia
Size: 2.7 inches (6.8 cm)

The Holy Cross Frog is a fossorial species of frog found in the  black soil plains and semi-arid grassland regions of western New South Wales and Queensland. During the dry times, the frog burrows down in the ground and surrounds itself in a cocoon to preserve water. They are capable of digging down almost 10 feet (3 meters)! Due to their fossorial lifestyle, the frogs feed primarily on ants and termites. When threatened by predators, the frogs produce a sticky, glue-like substance that predators don’t want to eat. It is advised to wash your hands after handling the Holy Cross Frog and basically any frog.

Once the heavy rains come, the frog will emerge from the ground, ready to breed. The male frogs will move to temporary ponds created by the rains and start to call out to females. The call sounds like a woo. Once the female arrives at the pond, the male glues himself to her back due to his smaller size. Next, the female lays her eggs and the male will fertilize them. Neither parents provide any parental care for their offspring.

Holy Cross Frog
photo by flickr user eyeweed

The International Union for the Conservation of Nature (IUCN) Red List categorizes the Holy Cross Frog as Least Concern for Extinction. The only threats to the species are habitat loss due to farming, climate change, and the introduction of the invasive Cane Toad (Rhinella marina). Researchers have been trying to get the frogs to breed in captivity just in case but have been struggling. Surprisingly, the answer to this problem was a Youtube Clip of a thunderstorm. This clip helps simulate heavy rain storms that gets the frogs in the mood.

Frog of the Week

Paradoxical Frog (Pseudis paradoxa)

Paradoxical Frog
photo by Hans Hillewaert
least concern

Common Name: Paradoxical Frog, Paradox Frog, Shrinking Frog
Scientific Name: Pseudis paradoxa
Family: Hylidae – Tree Frog Family
Locations:  Argentina, Bolivia, Brazil, Colombia, French Guiana, Guyana, Paraguay, Peru, Suriname, Trinidad and Tobago, and Venezuela
Size: 1.7 – 3 inches (45 – 75 mm)

The Paradoxical Frog is named after a strange phenomenon during their metamorphosis. Their tadpole is the largest tadpole in the world, almost reaching 10 inches (25 cm) long! That is over three times larger than the length of an adult frog! What a paradox! Yet, not all tadpoles exhibit the paradox. Tadpoles that are born in temporary bodies of water with predators transform quickly and leave the water before they get to massive sizes. In permanent bodies of water, they transform slower, thus allowing more growth time.

The Paradoxical Frog is a member of the Tree Frog family – Hylidae but they are never seen in the trees. They live in and around permanent and temporary ponds. These are the same bodies of water that they breed in. The males will call for the ponds for the females. Once the female arrives, the male will grasp her from behind in the amplexus position. Then, the female will start laying her eggs and the male will fertilize them. The eggs are laid in the vegetation near the shore. Neither parent provides any parental care.

The International Union for the Conservation of Nature (IUCN) Red List categorizes the Paradoxical Frog as Least Concern for Extinction. They have a wide spread range and are common throughout it. Some populations are facing declines due to habit loss due to urban development and agriculture.

Frog of the Week

Tarahumara Frog (Rana tarahumarae)

Tarahumara Frog
photo by Jim Rorabaugh of USFWS

Common Name: Tarahumara Frog
Scientific Name: Rana tarahumarae
Family: Ranidae – True Frog family
Locations: United States and Mexico
US Locations: Arizona
Size: 2.5 – 4 inches (64 – 102 mm)

The Tarahumara Frog is found in the montane canyons of southern Arizona and down into Mexico. Their main habitat is rocky streams and plunge pools. They breed in these permanent bodies of water from April to May. The male frog will call out to the females though they lack vocal sacs like other frogs have. The female will arrive and the male will grasp her from behind in the amplexus position. Then, the female will lay her eggs and the male will fertilize them. Females can lay up to 2200 eggs at a time. Neither parent will provide any parental care for their offspring. The tadpoles can take over 2 years to complete their metamorphosis.

The International Union for the Conservation of Nature (IUCN) Red Lists categorizes the Tarahumara Frog as Vulnerable to Extinction. The frog is extinct in Arizona and is steadily disappearing from Mexico. Chytrid Fungus, a deadly disease, is believed to have caused large die offs of the frogs. Other reasons for the declines in their numbers include invasive species, pollution, and habitat destruction. Invasive species, such as the Blue Gill and American Bullfrog, feast upon the frog and their tadpoles. Much of the range of the Tarahumara Frog in Arizona has been taken over by Bullfrogs.

There are currently projects working to reintroduce the frogs into Arizona. The first reintroduction was done in 2004. All of the frogs sadly died out over the next 10 years due to Chytrid Fungus and flooding. In 2012 and 2013, frogs and tadpoles were once again reintroduced but a die off happened due to chytrid fungus again. There’s still hope enough survived to continue the population. More plans for reintroduction are being considered.

Frog of the Week

Foothill Yellow-Legged Frog (Rana boylii)

photo by William Flaxington

Common Name: Foothill Yellow-Legged Frog
Scientific Name: Rana boylii
Family: Ranidae – True Frog family
Locations: United States
US Locations: California and Oregon
Size: 1.5 – 3.2 inches ( 3.8 – 8.1 cm)

The Foothill Yellow-Legged Frog is known for the yellow markings on the underside of their legs and extends to their belly. They live along the streams in the mountains of California and Oregon.

The breeding season starts at the end of March and continues to the end of May. Mating takes place in streams and rivers instead of the usual ponds and lakes that other frogs use. The males will call underwater to try to attract females. They do occasionally call above the water. Once the female selects a male, the male will grasp her from behind in the amplexus position. The female will lay between 300 – 2000 eggs, averaging around 900, and the male will then fertilize them.

Neither parent provides any parental care. The eggs hatch between 5 – 37 days days and the tadpoles transform between 3 and 4 months.Breeding end of March to start of May, streams rivers, males call underwater, 300 – 2,000, averaging 900. transform 3-4 months, hatch 5 – 37 days, typical breeding

The Foothill Yellow-Legged Frog is a candidate for the United States’ Endangered Species List and is already listed on the state of California’s Endangered Species List. The International Union for the Conservation of Nature (IUCN) Red List also lists them as Near Threatened. The frogs have disappeared from almost 45% of its range. Numerous different things have affected the frog’s populations. The large, introduced American Bullfrogs (Rana catesbeiana) feast upon any smaller frog than it, including the Foothill Yellow-Legged Frog. Introduced trout Pesticide use has decreased population numbers. Dams have altered the habitat that they call home.

Frog of the Week

Three-striped Poison Frog (Ameerega trivittata)

photo by Geoff Gallice 

Common Name: Three-striped Poison Frog
Scientific Name: Ameerega trivittata
Family: Dendrobatidae – Poison Dart Frog family
Locations: Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, and Venezuela
Size: 2 inches (50 mm) for females, 1.65 inches (42 mm)

The Three-striped Poison Frog is a diurnal species of frog found among the leaf litter in tropical rain forests. They are able to be active during the day thanks to their bright colors and their poison. The bright colors warn predators not to eat them due to their poison. They obtain their toxicity from the ants they eat in the wild. The stripes on the frog vary in color from green, yellow-green, yellow, to orange. Their beautiful colors make them attractive to pet owners. They lose their toxicity in captivity, making them safe. Always make sure to buy captive bred frogs from reputably breeders.

Reproduction happens year round but reaches its peak during the rainy season from May to October. Males will stake out territory on perches above the ground. The males will fight other males who enter their territory. Females select males on how long they have called on their territory and how large the territory is. Once the female selects a mate, the male will grasp the female from behind in amplexus. The female will lay the eggs under leaves and the male will then fertilize them. Females will lay between 15 – 30 eggs at a time.

photo by Shawn Mallan

The males of the species provide parental care for their offspring. The males will carry recently hatched tadpoles to water sources for them to live in until they complete their metamorphosis. The male will keep them on their backs for days until they find a spot. It takes the tadpoles between 41 to 54 days to complete their metamorphosis.

Frog of the Week

Green and Golden Bell Frog (Litoria aurea)

photo by LiquidGhoul

Common Name: Green and Golden Bell Frog
Scientific Name: Litoria aurea
Family: Hylidae – True Frog family
Locations: Australia
Introduced Locations: New Caledonia, New Zealand, and Vanuatu
Male Size: 2.2 – 2.7 inches (57 – 69 mm)
Female Size: 2.5 – 4.2 inches (65 – 108 mm)

While the Green and Golden Bell Frog is a member of the tree frog family, they are a semi-aquatic species of frog. They like to perch on vegetation around water. The frogs breed during summer time from October through March. Reproduction is pretty standard for these fellas. The males will call from the water and the female will select a mate. Then the male will grasp her from behind in the amplexus position and she will lay her eggs. The female frog lays between 3 – 10 thousand eggs. The male will then fertilize the eggs. Neither parent provides any care for their offspring.

The Green and Golden Bell Frog is naturally found along the southeastern coast of Australia but has expanded its range to other Pacific Islands including New Zealand. In New Zealand, they are found on the northern half of North Island. It’s hard to tell if these frogs are causing any problems in these new habitats.

The Green and Golden Bell Frog is listed as Vulnerable by the International Union for the Conservation of Nature (IUCN) Red List. The frogs face a variety of threats. The wetlands that the frogs live in are being drained to make room for more houses. The Mosquito Fish (Gambusia holbrooki) has been introduced to the wetlands as well to control mosquito populations. Sadly, these fish also feed on tadpoles of frogs. Also Red Foxes (Vulpes vulpes) has been introduced to Australia and they can feed on adult frogs. Chytrid Fungus, a deadly fungal pathogen that is devasting frog populations around the world, has been found in the frogs. This is likely causing some declines in the species.

Uncategorized

Brazilian Torrent Frog (Hylodes asper)

Common Name: Brazilian Torrent Frog
Scientific Name: Hylodes asper
Family: Hylodidae
Locations: Brazil
Size: 1.57 inches (40 mm)

The Brazilian Torrent Frog has one of the most sophisticated form of communication for a frog. The male of the species will pick a mating spot, high on rocks next to a busy stream. They will try to make mating or territorial calls but the stream is very loud behind them, drowning out their calls. The frogs have adapted a way to talk to the frogs over the sounds on the stream. The male frogs will raise their feet in a circular movement and show off their white toe pads. This is called foot flagging.

The males will do it to attract females and to warn other males to leave. If the other males don’t leave, they will fight it out for the spot with the loser hopping away. If a predator was to see the foot flagging and come after the male frog, the male will jump into the stream. This is a really quick getaway.

If a female picks a male to mate with, they will approach the male. The male will continue to call. The female will then stretch one or both of her legs backwards and move one hand up and down. The male will then touch her snout with his throat. Next to male will jump around the rocks and perform more foot flagging. He then jumps into the water followed by the female.

Uncategorized

Pacific Tree Frog (Pseudacris regilla)

photo by The High Fin Sperm Whale 

Common Name: Pacific Tree Frog, Pacific Chorus Frog
Scientific Name: Pseudacris regilla or Hyliola regilla
Family: Hylidae – Tree Frog family
Locations: Canada, Mexico, and the United States
US Locations: Alaska, Arizona, California, Idaho, Montana, Nevada, Oregon, Utah, and Washington
Size: .75 – 2 inches (19 – 50 mm)

Breeding for the frogs happen from November to July with frogs in higher elevations breeding later in the year. The male frogs will come to permanent or non-permanent waters bodies to start calling. The male frog’s breeding call is the typical ribbit that you hear on tv.

The males will highly territorial and will fight other males over breeding areas. Once the female comes and selects a mate, the male will grab her back in amplexus. The female will then lay her eggs and the male will fertilize them. The female will lay between 400 – 750 eggs at a time. Neither parent will provide any care for their offspring. The eggs hatch in 2 to 3 weeks. The tadpoles take 3 months to complete their transformation.

The Pacific Tree Frog was recently split into 3 different species based on DNA, but the analysis wasn’t great and it was merged back together.

The Pacific Tree Frog is the State Frog of Washington

Uncategorized

California Tree Frog (Pseudacris cadaverina)

photo by Chris Brown / USGS

Common Name: California Tree Frog or California Chorus Frog
Scientific Name: Pseudacris cadaverina or Hyliola cadaverina
Family: Hylidae – Tree Frog family
Locations: Mexico and the United States (California)
Male Size: 1.4 inches (36 mm)
Female Size: 1.8 inches (45 mm)

The California Tree Frog can be called the California Chorus Frog due to them being placed in the Chorus Frog genus – Pseudacris. Researchers have proposed moving the frog into the genus Hyliola along with the Pacific Chorus Frog. They are more similar to other Chorus Frogs, in that they aren’t found high in the trees. These frogs like to live in crevices or cavities in boulders along streams. The frogs blend into these boulders with their rough skin and gray / brown color.

Breeding takes place in the streams from February to October. Reproduction for the California Tree Frog is pretty standard. Males will call from the streams to attract potential mates. Once the female selects the mate, the male will grasp her from behind in amplexus. The female then lay her eggs and the male then fertilizes them. Neither parent provide any care for their offspring. The larval period for the tadpoles ranges from 40 – 75 days.

Frog of the Week

Coquí Llanero (Eleutherodactylus juanariveroi)

photo by the USFWS

Common Name: Coquí Llanero, Plains Coquí, or Puerto Rican Wetland Frog
Scientific Name: Eleutherodactylus juanariveroi
Family: Eleutherodactylidae
Locations: Puerto Rico
Average Male Size: .58 inches (14.7 mm)
Average Female Size: .62 inches (15.8 mm)

The Coquí Llanero was only recently described in 2005 by Neftalí Rios. It is found only in the wetlands in a old navy base in Toa Baja, Puerto Rico. Sadly, it is already listed as a federal endangered species and as critically endangered by the International Union for the Conservation of Nature (IUCN) Red List. They are listed due to their small habitat that is threatened by development. The wetlands have been designed as critical habitat but that offers little protection.

Now onto the biology of the frog. Like all members of the family Eleutherodactylidae, the Coquí Llanero lays eggs that directly develop into froglets, skipping the tadpole stage. Though, they lay one of the smallest clutches of eggs, ranging from 1 to 5. Interestingly, they only lay their eggs on the leaves of the Bulltongue Arrowhead (Sagittaria lancifolia). Breeding can happen year round though more clutches are produced in the warmer, wetter months. The call of the Coquí Llanero is the highest frequency of all amphibians on Puerto Rico, ranging between 7.38 and 8.28 kHz. This makes the calls nearly impossible to hear over all the other noises in the wetlands.